ES - CI9.1 Oxidation and Reduction

• Gain of electron = reduction
• Loss of electron = oxidation
• Reduction + oxidation = redox reaction
• Oxidising agent - accepts electrons - becomes reduced
• Reducing agent - donates electrons - becomes oxidised

eg.

Na + 1/2 Cl2 = Na+Cl-

Oxidation States

• Oxidation state - showing the charge an atom would have if all its bonds were ionic
• Metals react they lose an electron - oxidised - to form +ve ions = INCREASED oxidation number
• Non-metals gain an electron - reduced - to form -ve ions = DECREASED oxidation number
• Oxidation state will INCREASE BY…